I am using the on-module PHY for the Verdin IMX8MP. This is hooked up to the IMX8MP ENET_QOS peripheral to my understanding, which, in the embedded linux device tree, uses the ‘nxp,imx8mp-dwmac-eqos’ driver. I want to use this PHY for a PTP application with ptp4l, but I can never get the ptp4l system call to detect a foreign master clock (even though I can see the foreign master clock PTP multicast messages with tcpdump).
I tried to make a post on the NXP forum about this - one NXP employee who, initially did not seem to understand my question, claimed that only the fec-imx8mp driver supports PTP. I believe the fec-imx8mp driver is associated with the off-module PHY and the non-QOS ENET. Does this mean that there is no linux driver supporting PTP through the ENET_QOS and thus the on-module Verdin PHY? Hoping the NXP employee is confused/mistaken, so figured I would try asking here as well…
The nxp,imx8mp-dwmac-eqos driver should support PTP (Precision Time Protocol). The EQOS (Ethernet QoS) MAC on the i.MX8MP processor includes support for IEEE 1588-2008 Advanced Timestamping, which is essential for PTP. While we haven’t tested this ourselves, you can refer to this thread on the NXP community for more information.
Comically enough, that is my post. I still haven’t figured out how to get it working since the NXP responder thinks I care primarily about the PPS output rather than just whether it can see a foreign clock.
Update on this - pretty sure this was not a device tree issue but a configuration issue with the IMX8 clock and the test PTP device we were using. On a Wireshark examination, saw that the domain number for PTP was not matching between the 2 devices, causing the IMX8 to never detect a foreign master clock.
I have no experience with enabling PTP or working with PTP devices. However, after examining the driver source code, I can confirm that the nxp,imx8mp-dwmac-eqos driver does support PTP. While the part of the driver related to NXP hardware (drivers/net/ethernet/stmicro/stmmac/dwmac-imx.c) does not directly indicate PTP support, it is part of the stmmac driver suite, which does support PTP. Additionally, the iMX8M Plus device tree’s eqos node includes the ptp_ref clock.
